Transmission shifter mechanism



July 1, 1941. F GRQENE ETAL 2,247,491

TRANSMISSION SHIFTER MECHANISM,

Original Filed Nov. 12, 193? S'Sheets-Sheet l INVENTORS.

WILUAM F-GROENE HARRY C.KEMFER HOWARD EJJARB} ATTORNEY.

July 1, 1941. w. F. GROENE ET AL TRANSMISSION SHIFTER MECHANISM Origifial Filed Nov 12, 1937 6 Sheets-She et 2 5 mm of 9 HR g H b mm s F [5 mm .3 mm mr v 5 5 E mww F m n mm S 3 3 r 2. 5 mm 2 3 3 3 F 1% 3 Q I E. 8 8 E 2 5 5 3 a ma 5 m k Q: 7 m z w 2 m E mm a m mm mm 3 5 3 am ATTORNEY.

July 1, 1941. "w. F. GROENE ETAL TRANSMISSION SHIFTER MECHANISM Original Filed Nov. 12, 193.7 6.Sheets-Sheet 4 lNVENTORS.

W\\.L\I\M F. GROENE HARR; c KEMPER mm HOWA n EDARBT ATT 0 RN EY.

TRANSMISSION SHIFTER MECHANISM Original Filed Nov. 12, 1957 B Shee'tS-Sheet 5 g LL INVENTORS. \AHLLIAM FGRUENE HARRY CLKEMPER AND HOWARD EDKR'BY K ATTORNEY.

y 1941- w. F. GRO ENE ETAL TRANSMISSION SHIFTER.MECHANISM 6 Sheets-Sheet 6 Original Filed Nov. 12, 1937 GROENE ARRY QKEMPER DQARD EDRRBT ATTORNEY.

Patented July l, 1941 TRANSMISSEGN SHIFTER MECHANISM William F. Greene, Harry 0. Kemper, and Howard E. Darby, Cincinnati, Ohio, assignors to The R. K. Le Blond Machine Tool Company, Cincinnati, Ohio, a corporation of Delaware Original application November 12, 1937, Serial N 0. 174,216. Divided and this application August 22, 1939, Serial No. 291,424

4 Q'Jiaims.

This application is a divisional application of original application Serial No. 174,216 filed November 12, 1937.

The invention herein disclosed pertains to lathe headstocks and more particularly to manipulation and control of the change speed transmission mechanism in the headstock and the means for effecting the various speed changes.

Qne object of this invention is to provide in a lathe headstock transmission a pair of shiftable compound gears which may be actuated to provide low-back-gear and high-back-gear speeds with standard threads and feeds, high speed with fine threads and feeds, and low-back-gear speed with coarse threads for relieving.

Another object is to provide in a lathe a single lever for actuating the transmission whereby low-back-gear and high-back-gear speeds with standard threads and feeds, high speed with fine threads and feeds, and low-back-gear speed with coarse threads for relieving, may be quickly effected.

A still further object is to provide in a lathe having a series of speed changes, a plurality of levers which may be positioned while the lathe is in operation whereby a speed change may be preselected without stopping the operation of the lathe.

And still another object is to provide in a lathe transmission having a series of primary speed changes and a series of back-gear speed changes, a pair of control levers, one for each series of speed changes, for preselecting speed changes for one or both of said series.

Further features and advantages of our invention will be set forth in the following description of the drawings in which:

Figure I is a front elevation of the exterior of a headstock incorporating the features of our invention.

Figure II is a diagrammatic section through the transmission gearing incorporated in the headstock on the line II--II of Figures I11 and IV.

Figure III is a vertical transverse section through the headstock on the line III-III of Figures I, II, V and VI.

Figure IV is a vertical transverse section through the headstock on the line IVIV of Figures 1, II, V and VI.

Figure V is a plan view of the headstock with the top cover removed.

Figure VI is a vertical longitudinal section through the headstock on the line VI-VI of Figures III, IV and V.

Referring particularly to Figures II, III and IV, power for driving the headstock transmission is derived from the usual electric motor which is connected to the driving pulley l by suitable v-belts which operate in the grooves 2 in the pulley. The driving pulley i is fixed on the shaft 3 which is journaled on the bearing t and through the bevel gear 5 on the bearing 6 carried in the bracket '1 bolted to the rear of the headstock housing 3 by suitable screws 9. The bevel gear 5 engages and drives the bevel gear 19 fixed on the clutch shaft H journaled on bearings 12 and 13 carried in the headstock housing 55. Adjacent the bearing 12 is rotatably ,mounted, on the shaft ll, a 33-tooth gear It 15 which drives a EBB-tooth gear it through an idler gear (not shown), the gear 15 being fixed on a shaft l6 journaled on bearings 11 and 13 carried in the headstock housing 3. Adjacent the bearing 13 is rotatably mounted on a 36- tooth gear 19 which drives a Bil-tooth gear 26 fixed on the shaft 16. Multiple disc clutches 2i. and 22 are provided on shaft H for alternately causing one or the other of the respective gears It and 19 to be driven by the shaft ll whereby the shaft 16 through the gearing described, may be rotated in one direction or the other. A multiple disc rake 23 is also provided on the shaft H for arresting rotation of the shaft H when both of the clutches 2! and 22 are rendered inoperative.

On the shaft [6 is also fixed a 29-tooth gear 2 5 and a 33-tooth gear 25. On a splined shaft 26 journaled in bearings 21 and 28 carried in the headstock housing 8 is slidably mounted a cluster gear 29 comprising a 39-tooth gear 3G, a iii-tooth gear 31, and a 32-tooth gear 32 which gears may be selectively engaged with the respective gears 26, 24 and 25 whereby the shaft 25 may be rotated at three difierent speeds by the shaft It.

Also slidably mounted on the splined shaft 26 is a cluster gear 33 comprising an 18-tooth gear 34, a 36-tooth gear 35, and a 27-tooth gear 38, which gears may be selectively engaged with the respective 50-tooth gear 31, the 32-tooth gear 33, and the ll-tooth gear 39 fixed on the shaft ii] journaled in the bearings 41 and it carried in the headstock housing 8. Thus three different speed changes may be had between shaft 25 and shaft 40 or a total of nine speed changes may be effected between shaft 16 and shaft 40 by properly shifting the cluster gears 29 and 33, these speed changes being the nine primary speed changes of the headstock transmission.

The shaft 40 is coupled to the coaxial shaft it by the wide-faced iii-tooth gear 54, the shaft 43 being journaled in bearings 45 and 46 carried in the headstock housing 8 and having a widefaced l5-tooth pinion 47 formed integral therewith. Slidably mounted on a splined shaft 58 journaled in bearings 49 and 55 carried in the headstock housing 8 is a compound gear 5i comprising a large 65-tooth gear 52 and a 20- tooth pinion 53 which are adapted to be respectively engaged with the (SO-tooth gear 54 and the l05-tooth gear 55 fixed on the lathe spindle 56 which is journaled in bearings 5?, 53; and 59 in the headstock housing 8. The compound gear 5i may also be moved to a neutral position, as shown in Figure II, where neither of its'g'ears 5? and 53 engage the gears 54 and 55 on the lathe spindle 55. The gear 52 is at all times engaged with the pinion 41 on the shaft 53. When the gears 53 and 55 are engaged the spindle 56 is driven at low-back-gear speeds and when the gears 52 and 54 are engaged the spindle is driven at high-back-gear speeds.

"slidably'mounted on a splined shaft 5?] journaled in" bearings 6i and 52 carried in the headstock housing 8' is a compound gear 63 comprising the 42-tooth gear 54 and the 20-tooth pinion 65. On the spin'dle5t is fixed a double gear 56 having a wide faced 34-tooth gear 61 and a narrow faced 34-tooth gear 68. When the compound gear 65 is shifted to the position shown in Figure II, the gear 64 is engaged with the gear 55' and'the gear 61, as best seen in Figure IV, whereby the spindle is driven at high speed from the shaft 45 at which time the compound gear 51 is moved to neutral position rendering the low and high back gear drive inoperative.

When the spindle 56 is being driven at high speedf'roni shaft G through the gears 45, 65 and 67 itis desired to provide reduced rate of feed to the cutting tool. This is done by connecting the 20-tooth pinion 65 to the large 65-tooth gear 69 fixed'on the feed'reverse shaft ll], power from this shaft being transmitted through reversing gearing comprising the'gears H, 12 and'lB, and T4, and 75 to a feed box '15 mounted on the front of the lathe headstock 8 in a manner set forth in application Serial Number 84,500 filed June 10, 1936.

When it is desired to operate the lathe at very slow spindle speeds and with a coarse feed to the cutting tool as when it is to be used for coarse threading or relieving hobs, taps, etc., the compound backgear is shifted so that its pinion 53 is in mesh with the gear 55 on the spindle and the compound gear 53 is shifted so that, its gear 54 is disengaged from the gear 61 butre-' mainsengaged with gear 44 on the shaft 45 so that the's'pindle is rotated at low back gear speeds for coarse threading and relieving. In order to provide the coarse feed rate drive to the shaft 70 the gear 65 is also maintained in contact with the gear 59 as was done in the case of the fine feed with high spindle speeds described above. Since the drive from shaft 413 to shaft '10 is the same in both instances the provision of the coarse feed in the latter instance is accomplished by cutting the speed of rotation of the spindle relative to shaft 40 by utilizing the back gears 53 and 55 and disconnecting thehig'h speed driving gears'fifiand 57 When it is deisired to operate the lathe in low back gear or high back gear speeds with regular rates'o f feed for thecutting tool as in normal lathe turning operations, the compound back a i l hfl its jsq ei her gears. 53 nd-tear gears 52 and 54 are in mesh. Regular rates of feed in combination with these spindle speeds is accomplished by sliding the compound gear 63 so that its gear 54 is disengaged from both gears 54 and 51 and is connected as an idler gear between the 34-t0oth gear 63 and the lathe spindle and a similar 3 i-tooth gear ll fixed on the shaft 75, whereby the shaft iii and the spindle 56 rotate in synchronism, the gear being disengaged from the gear 55.

It will thus be seen that in this headstock transmission there are four elements to be actuated to obtain the various functions from the transmission. These elements comprise the cluster gears 29 and 33 which may be actuated by the control lever '58 and the compound gears 5i and 53 which may be actuated by the control lever '39, these levers being conveniently located at the front of the headstock housing 8 and having mechanism associated therewith for moving the various elements in proper sequence.

The lever 18 is fixed on a rock shaft 30 which is slidabvly mounted in bearings 8| and 82 in the headstock housing 8. On the shaft 89 are fixed operating cams 83 and 84 each having the respective peripheral cam surfaces 85 and 86. On

a pivot shaft B7 fixed in the headstock housing 5 is pivotally mounted a bell crank 83 one of its arms 89 being forked, as best shown in Figure VI, upon the ends of which are mounted rollers 90 and Si which are located on diametrically opposite sides of the shaft 85 and adapted to be en-. gaged by the peripheral cam surfaces 85 when the lever 78 is swung to clockwise position, Figure I and which rollers 58 and 98 are relieved from engagement from said cam surfaces when the lever i8 is swung to counterclockwise position, whereby the lever 73 may be pulled in and out to axially move the shaft 85 for presenting the various cam surfaces 85 to the rollers 59 and 9|. By this arrangement the arm 89 may be swung upward and downward different amounts depending upon the axial position of the shaft 80. The other downwardly extending arm 52 of the bell crank 8.8 is connected to a shifter rod 93 which carries a yoke 95 which engages the cluster gear 29 whereby manipulation of the lever it causes shifting of this cluster gear by the cam 85 as described. Suitable detent mechanism 95 4 associated with the shifter rod 93. maintains the cluster gear and its associated bell crank.

In a similar manner the cluster gear 33 is actuated by the cam 84. actuating the rollers 96 and 97 on the arm 58 of the bell crank lever 99 pivotally mounted on the shaft 81 and having a downwardly extending arm Hill connected to the shifter rod itl which carries a yoke I E12 engaging the compound gear 33. Detent mechanism I03 is also associated with the shifter rod Hll as for the rod 93.

The cams 83 and 8 are so arranged as to simultaneously actuate the cluster gears 29 and 33, in proper sequence for the various selected.

positions of the lever '18. A series of arcuate slots E55, provided inra bracket Hi5 fixed on the front of the headstock 8 by screws. I55 serve to axially position the shaft 80 andits lever 18 when the lever. is swung to clockwiseposition whereupon the locating lug lilfiA formedon the lever 18 has, entered one of the slots W4. An index plate lill is also associatedwith the locating slots tovindicate the Various speedsselected and is interrelated. with positions oflever 19.

In effecting speed changes the lever 18; is ;,;sw ung to counterclockwise. position and movedlin and out to the desired slot IM as shown by the index plate In! thus preselecting the next speed change to be made. During this movement of the lever I8 the speed change then in operation is not affected and continues to operate until the lever I8, at its newly selected position, is swung clockwise to rapidly put the newly preselected speed change in operation. Thus no time is lost in making selection of speed changes since the next desired speed change may be preselected while the lathe is still operating in the speed then in operation. It will also be noted that all of the primary speed changes in the headstock transmission may be affected by a single lever control.

The lever 19 for selecting the low-back-gear, high back gear, high speeding, and coarse threading and relieving speeds is arranged similarly to that of lever 18 described above. The lever 19 effects movements of the compound gears SI and 63, the lever I9 being fixed on a rock shaft I08 which is slidably mounted in bearings I09 and III! in the headstock housing 8. On the shaft I53 are fixed operating cams III and II2 each having the respective peripheral cam surfaces H3 and H4. On a pivot shaft IIE fixed in the headstock housing 8 is pivotally mounted a bell crank lever IIB, one of its arms In being forked, as best shown in Figure VI, having rollers H8 and H9 on the forked ends which may be engaged by the peripheral cam surfaces IE3 when lever I9 is swung to clockwise position and which rollers are relieved from engagement from. said surfaces when lever 19 is swung to counterclockwise position as in the case of lever iii. The other downwardly extending arm IZfl of bell crank IIB has a forked yoke I2I engaging in the annular slot I22 formed in the compound gear whereby manipulation of the lever I9 causes shifting of this cluster gear by the cam III as described. Detent mechanism I23 is provided in the compound gear 5| and maintains the cluster gear and its associated bell crank lever in any selected position set up by the actuating cam III.

In a similar manner the cluster gear 33 is actuated by the cam I I2 actuating the rollers I24 and I 25 and the arm I26 of the bell crank lever I21 pivotally mounted on the shaft I I5 and having a downwardly extending arm I28 connected to a shifter rod I 29 which carries a yoke I30 engaging the cluster gear 63. Detent mechanism I3! is associated with the shifter rod I29 for maintaining the cluster gear 63 and its associated bell crank I21 in shifted positions.

The cams III and H2 are so arranged as to simultaneously actuate the compound gears 5i and 63 in proper sequence for the Various selected positions of the lever 19. A series of arcuate slots I32, provided in a bracket I33 fixed on the front of the headstock 8 by screws I34 serve to axially position the shaft I68 and its lever I9 when the lever is swung to clockwise position whereupon the locating lug I35 formed on the lever 19 has entered one of the slots I32. An index plate I36 is also associated with the locating slots to indicate the various positions to be selected by the lever 18 already described.

Having fully set forth and described our invention, what we claim is:

1. In a change speed transmission having a plurality of shiftable elements, a single lever control mechanism for shifting said elements comprising a rock shaft slidably mounted in the housing for said transmission, cams on said shaft, and levers connected to the elements to be shifted and adapted to be actuated by said cams, and a lever on said shaft whereby axial movement and rotary movement of the lever in one direction effects preselection of the speed change desired while swinging of said lever in the opposite direction renders the speed change selected effective.

2. In a machine tool gear shifting mechanism, a housing, a shaft in said housing, a shiftable member on said shaft, a shifter rod rotatably and slidably mounted in said housing, a shifter lever mounted in said housing and connected to said shiftable member having a forked end straddling said rod, abutment portions on the ends of said forked portion, a cam having cam surfaces located on diametrically opposite sides of said rod adapted to engage said abutment portions, and a lever fixed on said rod to effect rocking and sliding of said shaft, said cam means being effective to actuate said shiftable member when said shifter rod is rotated in one direction and ineffective to actuate said member when said rod is rotated in the opposite direction.

3. In a machine tool gear shifting mechanism, a housing, a shaft in said housing, a shiftable member on said shaft, a shifter rod rotatablyand slidably mounted in said housing, a shifter lever mounted on said housing and connected to said shiftable member having a forked end straddling said rod, abutment portions on the ends of said forked portion, a cam having cam surfaces located on diametrically opposite sides of said rod adapted to engage said abutment portions when said rod is rotated in one direction, said cam being inoperative when said rod is rotated in the opposite direction, a manipulating lever fixed on said rod to effect rocking and sliding of said rod, and an index plate extending axially of said rod to indicate axial positions of sliding for said rod.

4. In a machine tool gear shifting mechanism, a housing, shafts in said housing, shiftable members on said shafts, a shifter rod rotatably and slidably mounted in said housing, shifter levers mounted in said housing and connected to said shiftable members having forked ends straddling said rod at axially spaced positions along said rod, abutment portions on the ends of said forked portions, axially spaced cams on said shifter rod having peripheral cam surfaces adapted to engage said abutment portions when said rod is rotated in one direction, said cams being inoperative when said rod is rotated in the opposite direction, a manipulating lever fixed on said rod, a series of positioning slots formed in said housing, a locating lug fixed on said rod adapted to be entered into said slots or removed therefrom by rocking said rod for axially positioning WILLIAM F. GROENE. HARRY C. KEMPER. HOWARD E. DARBY. 

